Excessive Caffeine Consumption in Children – Noteworthy Research Findings and Warnings

Caffeine is consumed through foods and creates a stimulating effect in the body by acting on the central nervous system (the brain). Caffeine, most commonly obtained from coffee and tea, is found in many packaged supermarket products such as cola, energy drinks, iced teas and chocolate. Although caffeine consumed within a certain amount does not harm the body, it can be harmful when the limit is exceeded.

The amount of caffeine children can tolerate is much lower than that of adults.

Excessive caffeine consumption can affect children's physical and mental health negatively. Parents should therefore be careful to limit caffeinated foods consumed by growing children.

What should the caffeine limit be for children?

Although the United States Food and Drug Administration (FDA) has set the daily caffeine amount for adults at 400 mg, it has not defined an upper limit for children. According to the American Academy of Pediactrics (American Academy of Pediatrics), which has 60,000 members from 68 countries:

• Children under 12 should not consume foods or drinks containing caffeine,
• Children over 12 should keep their daily caffeine consumption below 85-100 milligrams.

Health Canada, the Canadian government's department responsible for health, argues that caffeine limits for children should be:

• For children aged 4-6, a daily maximum of 45 mg,
• For children aged 7-9, a daily maximum of 62 mg,
• For children aged 10-12, a daily maximum of 85 mg should be observed.

In 2018, a study in Journal of Tourism and Gastronomy, conducted in Turkey, found that adolescents' daily average caffeine consumption was 172 mg.

Why is excessive caffeine consumption harmful in children?

Excessive caffeine consumption in children can cause insomnia, irritability, nausea, headaches, difficulty concentrating and an increased heart rate. In addition, childhood and adolescence are the most important years for bone development. By interfering with calcium absorption, excessive caffeine consumption can slow bone development. Caffeine's diuretic effect can also cause water and mineral loss in children who do not drink enough fluids and sweat heavily. In addition to all these adverse effects, the high sugar content of these drinks can increase the risk of many diseases, such as obesity, metabolic syndrome and diabetes.

The Journal of Pediatrics published a study in 2010 examining caffeine consumption in 228 children aged between 5 and 12 and their sleep quality using questionnaires completed by families and children. The study concluded that children's sleep duration was reduced.

Archives of Pediatrics and Adolescent Medicine published a study evaluating the relationship between caffeinated drink consumption and blood pressure. The 159 adolescent participants followed a sodium-restricted diet for 3 days. Their daily caffeine intake was classified as 0-50 mg, 50-100 mg and >100 mg. This study:

• Found that participants who consumed >100 mg of coffee daily showed an increase in systolic blood pressure,
• Concluded that caffeine had no effect on diastolic blood pressure.

In 2017, Journal of Clinical Sleep Medicine published a study investigating the effects of caffeine consumption on children's sleep patterns and behavior. The study, conducted with 309 children aged 8-12 and their families, concluded:

• There was an association between caffeine consumption, restless sleep syndrome and feeling tired in the mornings,
• Behavioral problems such as anxiety, depression, rule-breaking and aggressive behavior could increase.

The American Journal of Clinical Nutrition published another study investigating the effects of children's carbonated drink consumption on bones. The 228 participants, who were children and adolescents, were followed for 4 years. Children's carbonated drink consumption was assessed through food intake records, and bone mineral content was assessed by computed tomography. This study concluded:

• Long-term consumption of carbonated drinks, whether caffeinated or not, adversely affected children's bone structures.

Studies investigating the relationship between caffeine and health to date have generally involved adults. More scientific research is therefore needed to fully understand its effects on children and adolescents.

How much caffeine do drinks contain?

• 1 cup (65-75 ml) of Turkish coffee: an average of 60 mg
• 100 ml of filter coffee: 80-100 mg
• 100 ml of instant coffee: 30-40 mg
• 1 cup of espresso (50-60 ml): 70-130 mg
• 1 mug (200 ml) of black tea: 40-55 mg
• 1 mug (200 ml) of green tea: 30-50 mg
• 1 can (330 ml) of cola: 30-40 mg
• 1 can (330 ml) of ready-made iced tea: 15-25 mg
• 1 bottle (500 ml) of energy drink: 200-1250 mg
• 100 g of milk chocolate: 20 mg
• 100 g of dark chocolate: 40 mg
• 100 g of white chocolate: 0 mg

The caffeine content of the products above can be affected by many different factors. For example, the caffeine content of espresso beans can vary with processing practices, while that of chocolate can vary with its cocoa content. The values given below are therefore average values.

Which drinks provide the most caffeine to children and young people?

Today, children and young people obtain most of their caffeine from:

• Coffees with cream and syrups bought from large coffee chains,
• Cold soft drinks such as cola and iced tea,
• Energy drinks.

Comment / Summary

The recommended upper limit for caffeine in children is much lower than in adults. It can therefore be much easier for children to exceed this limit. In addition to caffeine, the high sugar content of drinks such as ready-made coffee, cola and iced tea can increase the risk of many diseases, particularly obesity. (You can read our article “Childhood Obesity and Its Even More Dangerous Consequences”). To minimize the amount of caffeine and sugar consumed, we can recommend introducing children to healthy drink alternatives (for the high sugar content of ready-made drinks and healthy drink recipes that can serve as alternatives, you can read our article “fluid consumption in children”).